1. Field
The present disclosure relates to an electrode active material, an electrode, and a secondary battery that include the electrode active material, and a method of preparing the electrode active material.
2. Description of the Related Art
A silicon-based material has received attention for use as an electrode active material for a high-capacity secondary battery because silicon has a theoretical capacity of about 3,570 milliAmpere hours per gram (mAh/g) at room temperature. However, the silicon-based material may undergo a volume expansion (up to about 300%) during intercalation and deintercalation of lithium ions.
The volume expansion of the silicon-based material may cause pulverization of the silicon-based material and mechanical strain associated with difficulties in controlling a solid electrolyte interphase (SEI) layer. Thus, an electrode active material including the silicon-based material may also cause a problem of sudden deterioration in charge and discharge characteristics, such as capacity and lifespan characteristics at initial steps, of a battery including the electrode active material.
To address such a problem above, the study of modification of a shape or structure of the silicon-based material, or the study of formation of a composite of the silicon-based material and other materials has been made with the objective of maintaining the high capacity of the silicon-based material and improving charge and discharge characteristics of a battery including the silicon-based material.
However, simple modification of a shape and/or structure of the silicon-based material or simple formation of a composite of the silicon-based material and other materials has not been shown sufficient to improve charge and discharge characteristics of a battery including the silicon-based material.
Therefore, there is still a need to develop an improved electrode active material, and a method of preparing the electrode active material.